/*
Minetest-c55
Copyright (C) 2010-2011 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "content_sao.h"
#include "collision.h"
#include "environment.h"
#include "settings.h"
#include "main.h" // For g_profiler
#include "profiler.h"
#include "serialization.h" // For compressZlib
#include "tool.h" // For ToolCapabilities
#include "gamedef.h"
#include "player.h"
#include "scriptapi.h"
#include "genericobject.h"

core::map<u16, ServerActiveObject::Factory> ServerActiveObject::m_types;

/*
	DummyLoadSAO
*/

class DummyLoadSAO : public ServerActiveObject
{
public:
	DummyLoadSAO(ServerEnvironment *env, v3f pos, u8 type):
		ServerActiveObject(env, pos)
	{
		ServerActiveObject::registerType(type, create);
	}
	// Pretend to be the test object (to fool the client)
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_TEST; }
	// And never save to disk
	bool isStaticAllowed() const
	{ return false; }
	
	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		return new DummyLoadSAO(env, pos, 0);
	}

	void step(float dtime, bool send_recommended)
	{
		m_removed = true;
		infostream<<"DummyLoadSAO step"<<std::endl;
	}

private:
};

// Prototype (registers item for deserialization)
DummyLoadSAO proto1_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_RAT);
DummyLoadSAO proto2_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_OERKKI1);
DummyLoadSAO proto3_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_FIREFLY);
DummyLoadSAO proto4_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_MOBV2);

/*
	TestSAO
*/

class TestSAO : public ServerActiveObject
{
public:
	TestSAO(ServerEnvironment *env, v3f pos):
		ServerActiveObject(env, pos),
		m_timer1(0),
		m_age(0)
	{
		ServerActiveObject::registerType(getType(), create);
	}
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_TEST; }
	
	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		return new TestSAO(env, pos);
	}

	void step(float dtime, bool send_recommended)
	{
		m_age += dtime;
		if(m_age > 10)
		{
			m_removed = true;
			return;
		}

		m_base_position.Y += dtime * BS * 2;
		if(m_base_position.Y > 8*BS)
			m_base_position.Y = 2*BS;

		if(send_recommended == false)
			return;

		m_timer1 -= dtime;
		if(m_timer1 < 0.0)
		{
			m_timer1 += 0.125;

			std::string data;

			data += itos(0); // 0 = position
			data += " ";
			data += itos(m_base_position.X);
			data += " ";
			data += itos(m_base_position.Y);
			data += " ";
			data += itos(m_base_position.Z);

			ActiveObjectMessage aom(getId(), false, data);
			m_messages_out.push_back(aom);
		}
	}

private:
	float m_timer1;
	float m_age;
};

// Prototype (registers item for deserialization)
TestSAO proto_TestSAO(NULL, v3f(0,0,0));

/*
	ItemSAO
*/

class ItemSAO : public ServerActiveObject
{
public:
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_ITEM; }
	
	float getMinimumSavedMovement()
	{ return 0.1*BS; }

	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		std::istringstream is(data, std::ios::binary);
		char buf[1];
		// read version
		is.read(buf, 1);
		u8 version = buf[0];
		// check if version is supported
		if(version != 0)
			return NULL;
		std::string itemstring = deSerializeString(is);
		infostream<<"create(): Creating item \""
				<<itemstring<<"\""<<std::endl;
		return new ItemSAO(env, pos, itemstring);
	}

	ItemSAO(ServerEnvironment *env, v3f pos,
			const std::string itemstring):
		ServerActiveObject(env, pos),
		m_itemstring(itemstring),
		m_itemstring_changed(false),
		m_speed_f(0,0,0),
		m_last_sent_position(0,0,0)
	{
		ServerActiveObject::registerType(getType(), create);
	}

	void step(float dtime, bool send_recommended)
	{
		ScopeProfiler sp2(g_profiler, "step avg", SPT_AVG);

		assert(m_env);

		const float interval = 0.2;
		if(m_move_interval.step(dtime, interval)==false)
			return;
		dtime = interval;
		
		core::aabbox3d<f32> box(-BS/3.,0.0,-BS/3., BS/3.,BS*2./3.,BS/3.);
		collisionMoveResult moveresult;
		// Apply gravity
		m_speed_f += v3f(0, -dtime*9.81*BS, 0);
		// Maximum movement without glitches
		f32 pos_max_d = BS*0.25;
		// Limit speed
		if(m_speed_f.getLength()*dtime > pos_max_d)
			m_speed_f *= pos_max_d / (m_speed_f.getLength()*dtime);
		v3f pos_f = getBasePosition();
		v3f pos_f_old = pos_f;
		IGameDef *gamedef = m_env->getGameDef();
		moveresult = collisionMoveSimple(&m_env->getMap(), gamedef,
				pos_max_d, box, dtime, pos_f, m_speed_f);
		
		if(send_recommended == false)
			return;

		if(pos_f.getDistanceFrom(m_last_sent_position) > 0.05*BS)
		{
			setBasePosition(pos_f);
			m_last_sent_position = pos_f;

			std::ostringstream os(std::ios::binary);
			// command (0 = update position)
			writeU8(os, 0);
			// pos
			writeV3F1000(os, m_base_position);
			// create message and add to list
			ActiveObjectMessage aom(getId(), false, os.str());
			m_messages_out.push_back(aom);
		}
		if(m_itemstring_changed)
		{
			m_itemstring_changed = false;

			std::ostringstream os(std::ios::binary);
			// command (1 = update itemstring)
			writeU8(os, 1);
			// itemstring
			os<<serializeString(m_itemstring);
			// create message and add to list
			ActiveObjectMessage aom(getId(), false, os.str());
			m_messages_out.push_back(aom);
		}
	}

	std::string getClientInitializationData()
	{
		std::ostringstream os(std::ios::binary);
		// version
		writeU8(os, 0);
		// pos
		writeV3F1000(os, m_base_position);
		// itemstring
		os<<serializeString(m_itemstring);
		return os.str();
	}

	std::string getStaticData()
	{
		infostream<<__FUNCTION_NAME<<std::endl;
		std::ostringstream os(std::ios::binary);
		// version
		writeU8(os, 0);
		// itemstring
		os<<serializeString(m_itemstring);
		return os.str();
	}

	ItemStack createItemStack()
	{
		try{
			IItemDefManager *idef = m_env->getGameDef()->idef();
			ItemStack item;
			item.deSerialize(m_itemstring, idef);
			infostream<<__FUNCTION_NAME<<": m_itemstring=\""<<m_itemstring
					<<"\" -> item=\""<<item.getItemString()<<"\""
					<<std::endl;
			return item;
		}
		catch(SerializationError &e)
		{
			infostream<<__FUNCTION_NAME<<": serialization error: "
					<<"m_itemstring=\""<<m_itemstring<<"\""<<std::endl;
			return ItemStack();
		}
	}

	int punch(v3f dir,
			const ToolCapabilities *toolcap,
			ServerActiveObject *puncher,
			float time_from_last_punch)
	{
		// Directly delete item in creative mode
		if(g_settings->getBool("creative_mode") == true)
		{
			m_removed = true;
			return 0;
		}
		
		// Take item into inventory
		ItemStack item = createItemStack();
		Inventory *inv = puncher->getInventory();
		if(inv != NULL)
		{
			std::string wieldlist = puncher->getWieldList();
			ItemStack leftover = inv->addItem(wieldlist, item);
			puncher->setInventoryModified();
			if(leftover.empty())
			{
				m_removed = true;
			}
			else
			{
				m_itemstring = leftover.getItemString();
				m_itemstring_changed = true;
			}
		}
		
		return 0;
	}


private:
	std::string m_itemstring;
	bool m_itemstring_changed;
	v3f m_speed_f;
	v3f m_last_sent_position;
	IntervalLimiter m_move_interval;
};

// Prototype (registers item for deserialization)
ItemSAO proto_ItemSAO(NULL, v3f(0,0,0), "");

ServerActiveObject* createItemSAO(ServerEnvironment *env, v3f pos,
		const std::string itemstring)
{
	return new ItemSAO(env, pos, itemstring);
}

/*
	LuaEntitySAO
*/

// Prototype (registers item for deserialization)
LuaEntitySAO proto_LuaEntitySAO(NULL, v3f(0,0,0), "_prototype", "");

LuaEntitySAO::LuaEntitySAO(ServerEnvironment *env, v3f pos,
		const std::string &name, const std::string &state):
	ServerActiveObject(env, pos),
	m_init_name(name),
	m_init_state(state),
	m_registered(false),
	m_hp(-1),
	m_velocity(0,0,0),
	m_acceleration(0,0,0),
	m_yaw(0),
	m_properties_sent(true),
	m_last_sent_yaw(0),
	m_last_sent_position(0,0,0),
	m_last_sent_velocity(0,0,0),
	m_last_sent_position_timer(0),
	m_last_sent_move_precision(0),
	m_armor_groups_sent(false)
{
	// Only register type if no environment supplied
	if(env == NULL){
		ServerActiveObject::registerType(getType(), create);
		return;
	}
	
	// Initialize something to armor groups
	m_armor_groups["fleshy"] = 3;
	m_armor_groups["snappy"] = 2;
}

LuaEntitySAO::~LuaEntitySAO()
{
	if(m_registered){
		lua_State *L = m_env->getLua();
		scriptapi_luaentity_rm(L, m_id);
	}
}

void LuaEntitySAO::addedToEnvironment()
{
	ServerActiveObject::addedToEnvironment();
	
	// Create entity from name
	lua_State *L = m_env->getLua();
	m_registered = scriptapi_luaentity_add(L, m_id, m_init_name.c_str());
	
	if(m_registered){
		// Get properties
		scriptapi_luaentity_get_properties(L, m_id, &m_prop);
		// Initialize HP from properties
		m_hp = m_prop.hp_max;
		// Activate entity, supplying serialized state
		scriptapi_luaentity_activate(L, m_id, m_init_state.c_str());
	}
}

ServerActiveObject* LuaEntitySAO::create(ServerEnvironment *env, v3f pos,
		const std::string &data)
{
	std::string name;
	std::string state;
	s16 hp = 1;
	v3f velocity;
	float yaw = 0;
	if(data != ""){
		std::istringstream is(data, std::ios::binary);
		// read version
		u8 version = readU8(is);
		// check if version is supported
		if(version == 0){
			name = deSerializeString(is);
			state = deSerializeLongString(is);
		}
		else if(version == 1){
			name = deSerializeString(is);
			state = deSerializeLongString(is);
			hp = readS16(is);
			velocity = readV3F1000(is);
			yaw = readF1000(is);
		}
	}
	// create object
	infostream<<"LuaEntitySAO::create(name=\""<<name<<"\" state=\""
			<<state<<"\")"<<std::endl;
	LuaEntitySAO *sao = new LuaEntitySAO(env, pos, name, state);
	sao->m_hp = hp;
	sao->m_velocity = velocity;
	sao->m_yaw = yaw;
	return sao;
}

void LuaEntitySAO::step(float dtime, bool send_recommended)
{
	if(!m_properties_sent)
	{
		m_properties_sent = true;
		std::string str = getPropertyPacket();
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}

	m_last_sent_position_timer += dtime;
	
	if(m_prop.physical){
		core::aabbox3d<f32> box = m_prop.collisionbox;
		box.MinEdge *= BS;
		box.MaxEdge *= BS;
		collisionMoveResult moveresult;
		f32 pos_max_d = BS*0.25; // Distance per iteration
		v3f p_pos = getBasePosition();
		v3f p_velocity = m_velocity;
		IGameDef *gamedef = m_env->getGameDef();
		moveresult = collisionMovePrecise(&m_env->getMap(), gamedef,
				pos_max_d, box, dtime, p_pos, p_velocity);
		// Apply results
		setBasePosition(p_pos);
		m_velocity = p_velocity;

		m_velocity += dtime * m_acceleration;
	} else {
		m_base_position += dtime * m_velocity + 0.5 * dtime
				* dtime * m_acceleration;
		m_velocity += dtime * m_acceleration;
	}

	if(m_registered){
		lua_State *L = m_env->getLua();
		scriptapi_luaentity_step(L, m_id, dtime);
	}

	if(send_recommended == false)
		return;
	
	// TODO: force send when acceleration changes enough?
	float minchange = 0.2*BS;
	if(m_last_sent_position_timer > 1.0){
		minchange = 0.01*BS;
	} else if(m_last_sent_position_timer > 0.2){
		minchange = 0.05*BS;
	}
	float move_d = m_base_position.getDistanceFrom(m_last_sent_position);
	move_d += m_last_sent_move_precision;
	float vel_d = m_velocity.getDistanceFrom(m_last_sent_velocity);
	if(move_d > minchange || vel_d > minchange ||
			fabs(m_yaw - m_last_sent_yaw) > 1.0){
		sendPosition(true, false);
	}

	if(m_armor_groups_sent == false){
		m_armor_groups_sent = true;
		std::string str = gob_cmd_update_armor_groups(
				m_armor_groups);
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}
}

std::string LuaEntitySAO::getClientInitializationData()
{
	std::ostringstream os(std::ios::binary);
	writeU8(os, 0); // version
	os<<serializeString(""); // name
	writeU8(os, 0); // is_player
	writeV3F1000(os, m_base_position);
	writeF1000(os, m_yaw);
	writeS16(os, m_hp);
	writeU8(os, 2); // number of messages stuffed in here
	os<<serializeLongString(getPropertyPacket()); // message 1
	os<<serializeLongString(gob_cmd_update_armor_groups(m_armor_groups)); // 2
	// return result
	return os.str();
}

std::string LuaEntitySAO::getStaticData()
{
	verbosestream<<__FUNCTION_NAME<<std::endl;
	std::ostringstream os(std::ios::binary);
	// version
	writeU8(os, 1);
	// name
	os<<serializeString(m_init_name);
	// state
	if(m_registered){
		lua_State *L = m_env->getLua();
		std::string state = scriptapi_luaentity_get_staticdata(L, m_id);
		os<<serializeLongString(state);
	} else {
		os<<serializeLongString(m_init_state);
	}
	// hp
	writeS16(os, m_hp);
	// velocity
	writeV3F1000(os, m_velocity);
	// yaw
	writeF1000(os, m_yaw);
	return os.str();
}

int LuaEntitySAO::punch(v3f dir,
		const ToolCapabilities *toolcap,
		ServerActiveObject *puncher,
		float time_from_last_punch)
{
	if(!m_registered){
		// Delete unknown LuaEntities when punched
		m_removed = true;
		return 0;
	}
	
	ItemStack *punchitem = NULL;
	ItemStack punchitem_static;
	if(puncher){
		punchitem_static = puncher->getWieldedItem();
		punchitem = &punchitem_static;
	}

	PunchDamageResult result = getPunchDamage(
			m_armor_groups,
			toolcap,
			punchitem,
			time_from_last_punch);
	
	if(result.did_punch)
	{
		setHP(getHP() - result.damage);
		
		actionstream<<getDescription()<<" punched by "
				<<puncher->getDescription()<<", damage "<<result.damage
				<<" hp, health now "<<getHP()<<" hp"<<std::endl;
		
		{
			std::string str = gob_cmd_punched(result.damage, getHP());
			// create message and add to list
			ActiveObjectMessage aom(getId(), true, str);
			m_messages_out.push_back(aom);
		}

		if(getHP() == 0)
			m_removed = true;
	}

	lua_State *L = m_env->getLua();
	scriptapi_luaentity_punch(L, m_id, puncher,
			time_from_last_punch, toolcap, dir);

	return result.wear;
}

void LuaEntitySAO::rightClick(ServerActiveObject *clicker)
{
	if(!m_registered)
		return;
	lua_State *L = m_env->getLua();
	scriptapi_luaentity_rightclick(L, m_id, clicker);
}

void LuaEntitySAO::setPos(v3f pos)
{
	m_base_position = pos;
	sendPosition(false, true);
}

void LuaEntitySAO::moveTo(v3f pos, bool continuous)
{
	m_base_position = pos;
	if(!continuous)
		sendPosition(true, true);
}

float LuaEntitySAO::getMinimumSavedMovement()
{
	return 0.1 * BS;
}

std::string LuaEntitySAO::getDescription()
{
	std::ostringstream os(std::ios::binary);
	os<<"LuaEntitySAO at (";
	os<<(m_base_position.X/BS)<<",";
	os<<(m_base_position.Y/BS)<<",";
	os<<(m_base_position.Z/BS);
	os<<")";
	return os.str();
}

void LuaEntitySAO::setHP(s16 hp)
{
	if(hp < 0) hp = 0;
	m_hp = hp;
}

s16 LuaEntitySAO::getHP() const
{
	return m_hp;
}

void LuaEntitySAO::setArmorGroups(const ItemGroupList &armor_groups)
{
	m_armor_groups = armor_groups;
	m_armor_groups_sent = false;
}

ObjectProperties* LuaEntitySAO::accessObjectProperties()
{
	return &m_prop;
}

void LuaEntitySAO::notifyObjectPropertiesModified()
{
	m_properties_sent = false;
}

void LuaEntitySAO::setVelocity(v3f velocity)
{
	m_velocity = velocity;
}

v3f LuaEntitySAO::getVelocity()
{
	return m_velocity;
}

void LuaEntitySAO::setAcceleration(v3f acceleration)
{
	m_acceleration = acceleration;
}

v3f LuaEntitySAO::getAcceleration()
{
	return m_acceleration;
}

void LuaEntitySAO::setYaw(float yaw)
{
	m_yaw = yaw;
}

float LuaEntitySAO::getYaw()
{
	return m_yaw;
}

void LuaEntitySAO::setTextureMod(const std::string &mod)
{
	std::string str = gob_cmd_set_texture_mod(mod);
	// create message and add to list
	ActiveObjectMessage aom(getId(), true, str);
	m_messages_out.push_back(aom);
}

void LuaEntitySAO::setSprite(v2s16 p, int num_frames, float framelength,
		bool select_horiz_by_yawpitch)
{
	std::string str = gob_cmd_set_sprite(
		p,
		num_frames,
		framelength,
		select_horiz_by_yawpitch
	);
	// create message and add to list
	ActiveObjectMessage aom(getId(), true, str);
	m_messages_out.push_back(aom);
}

std::string LuaEntitySAO::getName()
{
	return m_init_name;
}

std::string LuaEntitySAO::getPropertyPacket()
{
	return gob_cmd_set_properties(m_prop);
}

void LuaEntitySAO::sendPosition(bool do_interpolate, bool is_movement_end)
{
	m_last_sent_move_precision = m_base_position.getDistanceFrom(
			m_last_sent_position);
	m_last_sent_position_timer = 0;
	m_last_sent_yaw = m_yaw;
	m_last_sent_position = m_base_position;
	m_last_sent_velocity = m_velocity;
	//m_last_sent_acceleration = m_acceleration;

	float update_interval = m_env->getSendRecommendedInterval();

	std::string str = gob_cmd_update_position(
		m_base_position,
		m_velocity,
		m_acceleration,
		m_yaw,
		do_interpolate,
		is_movement_end,
		update_interval
	);
	// create message and add to list
	ActiveObjectMessage aom(getId(), false, str);
	m_messages_out.push_back(aom);
}

/*
	PlayerSAO
*/

// No prototype, PlayerSAO does not need to be deserialized

PlayerSAO::PlayerSAO(ServerEnvironment *env_, Player *player_, u16 peer_id_,
		const std::set<std::string> &privs, bool is_singleplayer):
	ServerActiveObject(env_, v3f(0,0,0)),
	m_player(player_),
	m_peer_id(peer_id_),
	m_inventory(NULL),
	m_last_good_position(0,0,0),
	m_last_good_position_age(0),
	m_time_from_last_punch(0),
	m_wield_index(0),
	m_position_not_sent(false),
	m_armor_groups_sent(false),
	m_properties_sent(true),
	m_privs(privs),
	m_is_singleplayer(is_singleplayer),
	// public
	m_teleported(false),
	m_inventory_not_sent(false),
	m_hp_not_sent(false),
	m_wielded_item_not_sent(false)
{
	assert(m_player);
	assert(m_peer_id != 0);
	setBasePosition(m_player->getPosition());
	m_inventory = &m_player->inventory;
	m_armor_groups["choppy"] = 2;
	m_armor_groups["fleshy"] = 3;

	m_prop.hp_max = PLAYER_MAX_HP;
	m_prop.physical = false;
	m_prop.weight = 75;
	m_prop.collisionbox = core::aabbox3d<f32>(-1/3.,-1.0,-1/3., 1/3.,1.0,1/3.);
	m_prop.visual = "upright_sprite";
	m_prop.visual_size = v2f(1, 2);
	m_prop.textures.clear();
	m_prop.textures.push_back("player.png");
	m_prop.textures.push_back("player_back.png");
	m_prop.spritediv = v2s16(1,1);
	m_prop.is_visible = (getHP() != 0);
	m_prop.makes_footstep_sound = true;
}

PlayerSAO::~PlayerSAO()
{
	if(m_inventory != &m_player->inventory)
		delete m_inventory;

}

std::string PlayerSAO::getDescription()
{
	return std::string("player ") + m_player->getName();
}

// Called after id has been set and has been inserted in environment
void PlayerSAO::addedToEnvironment()
{
	ServerActiveObject::addedToEnvironment();
	ServerActiveObject::setBasePosition(m_player->getPosition());
	m_player->setPlayerSAO(this);
	m_player->peer_id = m_peer_id;
	m_last_good_position = m_player->getPosition();
	m_last_good_position_age = 0.0;
}

// Called before removing from environment
void PlayerSAO::removingFromEnvironment()
{
	ServerActiveObject::removingFromEnvironment();
	if(m_player->getPlayerSAO() == this)
	{
		m_player->setPlayerSAO(NULL);
		m_player->peer_id = 0;
	}
}

bool PlayerSAO::isStaticAllowed() const
{
	return false;
}

bool PlayerSAO::unlimitedTransferDistance() const
{
	return g_settings->getBool("unlimited_player_transfer_distance");
}

std::string PlayerSAO::getClientInitializationData()
{
	std::ostringstream os(std::ios::binary);
	writeU8(os, 0); // version
	os<<serializeString(m_player->getName()); // name
	writeU8(os, 1); // is_player
	writeV3F1000(os, m_player->getPosition() + v3f(0,BS*1,0));
	writeF1000(os, m_player->getYaw());
	writeS16(os, getHP());
	writeU8(os, 2); // number of messages stuffed in here
	os<<serializeLongString(getPropertyPacket()); // message 1
	os<<serializeLongString(gob_cmd_update_armor_groups(m_armor_groups)); // 2
	return os.str();
}

std::string PlayerSAO::getStaticData()
{
	assert(0);
	return "";
}

void PlayerSAO::step(float dtime, bool send_recommended)
{
	if(!m_properties_sent)
	{
		m_properties_sent = true;
		std::string str = getPropertyPacket();
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}

	m_time_from_last_punch += dtime;
	
	if(m_is_singleplayer)
	{
		m_last_good_position = m_player->getPosition();
		m_last_good_position_age = 0;
	}
	else
	{
		/*
			Check player movements

			NOTE: Actually the server should handle player physics like the
			client does and compare player's position to what is calculated
			on our side. This is required when eg. players fly due to an
			explosion.
		*/

		float player_max_speed = 0;
		float player_max_speed_up = 0;
		if(m_privs.count("fast") != 0){
			// Fast speed
			player_max_speed = BS * 20;
			player_max_speed_up = BS * 20;
		} else {
			// Normal speed
			player_max_speed = BS * 4.0;
			player_max_speed_up = BS * 4.0;
		}
		// Tolerance
		player_max_speed *= 2.5;
		player_max_speed_up *= 2.5;

		m_last_good_position_age += dtime;
		if(m_last_good_position_age >= 1.0){
			float age = m_last_good_position_age;
			v3f diff = (m_player->getPosition() - m_last_good_position);
			float d_vert = diff.Y;
			diff.Y = 0;
			float d_horiz = diff.getLength();
			/*infostream<<m_player->getName()<<"'s horizontal speed is "
					<<(d_horiz/age)<<std::endl;*/
			if(d_horiz <= age * player_max_speed &&
					(d_vert < 0 || d_vert < age * player_max_speed_up)){
				m_last_good_position = m_player->getPosition();
			} else {
				actionstream<<"Player "<<m_player->getName()
						<<" moved too fast; resetting position"
						<<std::endl;
				m_player->setPosition(m_last_good_position);
				m_teleported = true;
			}
			m_last_good_position_age = 0;
		}
	}

	if(send_recommended == false)
		return;

	if(m_position_not_sent)
	{
		m_position_not_sent = false;
		float update_interval = m_env->getSendRecommendedInterval();
		std::string str = gob_cmd_update_position(
			m_player->getPosition() + v3f(0,BS*1,0),
			v3f(0,0,0),
			v3f(0,0,0),
			m_player->getYaw(),
			true,
			false,
			update_interval
		);
		// create message and add to list
		ActiveObjectMessage aom(getId(), false, str);
		m_messages_out.push_back(aom);
	}

	if(m_wielded_item_not_sent)
	{
		m_wielded_item_not_sent = false;
		// GenericCAO has no special way to show this
	}

	if(m_armor_groups_sent == false){
		m_armor_groups_sent = true;
		std::string str = gob_cmd_update_armor_groups(
				m_armor_groups);
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}
}

void PlayerSAO::setBasePosition(const v3f &position)
{
	ServerActiveObject::setBasePosition(position);
	m_position_not_sent = true;
}

void PlayerSAO::setPos(v3f pos)
{
	m_player->setPosition(pos);
	// Movement caused by this command is always valid
	m_last_good_position = pos;
	m_last_good_position_age = 0;
	// Force position change on client
	m_teleported = true;
}

void PlayerSAO::moveTo(v3f pos, bool continuous)
{
	m_player->setPosition(pos);
	// Movement caused by this command is always valid
	m_last_good_position = pos;
	m_last_good_position_age = 0;
	// Force position change on client
	m_teleported = true;
}

int PlayerSAO::punch(v3f dir,
	const ToolCapabilities *toolcap,
	ServerActiveObject *puncher,
	float time_from_last_punch)
{
	if(!toolcap)
		return 0;

	// No effect if PvP disabled
	if(g_settings->getBool("enable_pvp") == false){
		if(puncher->getType() == ACTIVEOBJECT_TYPE_PLAYER){
			std::string str = gob_cmd_punched(0, getHP());
			// create message and add to list
			ActiveObjectMessage aom(getId(), true, str);
			m_messages_out.push_back(aom);
			return 0;
		}
	}

	HitParams hitparams = getHitParams(m_armor_groups, toolcap,
			time_from_last_punch);

	actionstream<<"Player "<<m_player->getName()<<" punched by "
			<<puncher->getDescription()<<", damage "<<hitparams.hp
			<<" HP"<<std::endl;

	setHP(getHP() - hitparams.hp);

	if(hitparams.hp != 0)
	{
		std::string str = gob_cmd_punched(hitparams.hp, getHP());
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}

	return hitparams.wear;
}

void PlayerSAO::rightClick(ServerActiveObject *clicker)
{
}

s16 PlayerSAO::getHP() const
{
	return m_player->hp;
}

void PlayerSAO::setHP(s16 hp)
{
	s16 oldhp = m_player->hp;

	if(hp < 0)
		hp = 0;
	else if(hp > PLAYER_MAX_HP)
		hp = PLAYER_MAX_HP;

	if(hp < oldhp && g_settings->getBool("enable_damage") == false)
	{
		m_hp_not_sent = true; // fix wrong prediction on client
		return;
	}

	m_player->hp = hp;

	if(hp != oldhp)
		m_hp_not_sent = true;

	// On death or reincarnation send an active object message
	if((hp == 0) != (oldhp == 0))
	{
		// Will send new is_visible value based on (getHP()!=0)
		m_properties_sent = false;
		// Send new HP
		std::string str = gob_cmd_punched(0, getHP());
		ActiveObjectMessage aom(getId(), true, str);
		m_messages_out.push_back(aom);
	}
}

void PlayerSAO::setArmorGroups(const ItemGroupList &armor_groups)
{
	m_armor_groups = armor_groups;
	m_armor_groups_sent = false;
}

ObjectProperties* PlayerSAO::accessObjectProperties()
{
	return &m_prop;
}

void PlayerSAO::notifyObjectPropertiesModified()
{
	m_properties_sent = false;
}

Inventory* PlayerSAO::getInventory()
{
	return m_inventory;
}
const Inventory* PlayerSAO::getInventory() const
{
	return m_inventory;
}

InventoryLocation PlayerSAO::getInventoryLocation() const
{
	InventoryLocation loc;
	loc.setPlayer(m_player->getName());
	return loc;
}

void PlayerSAO::setInventoryModified()
{
	m_inventory_not_sent = true;
}

std::string PlayerSAO::getWieldList() const
{
	return "main";
}

int PlayerSAO::getWieldIndex() const
{
	return m_wield_index;
}

void PlayerSAO::setWieldIndex(int i)
{
	if(i != m_wield_index)
	{
		m_wield_index = i;
		m_wielded_item_not_sent = true;
	}
}

void PlayerSAO::disconnected()
{
	m_peer_id = 0;
	m_removed = true;
	if(m_player->getPlayerSAO() == this)
	{
		m_player->setPlayerSAO(NULL);
		m_player->peer_id = 0;
	}
}

void PlayerSAO::createCreativeInventory()
{
	if(m_inventory != &m_player->inventory)
		delete m_inventory;

	m_inventory = new Inventory(m_player->inventory);
	m_inventory->clearContents();
	scriptapi_get_creative_inventory(m_env->getLua(), this);
}

std::string PlayerSAO::getPropertyPacket()
{
	m_prop.is_visible = (getHP() != 0);
	return gob_cmd_set_properties(m_prop);
}

